Most of the currently used analgesic drugs fall into the categories of
opioids and nonsteroidal antiinflammatory drugs such as COX-2
inhibitors. Non-opioid analgesics include ketamine, a
N-methyl-D-aspartate receptor antagonist. Adjuvant analgesics include
antidepressants and antiepileptic drugs used for the treatment of
neuropathic pain. Management of pain is multidisciplinary and includes
both pharmacological and non-pharmacological methods such as
acupuncture, transcutaneous electrical nerve stimulation and surgery.
Various pain syndromes require different approaches in management, for
example, the main category of drugs for migraine are triptans such as
sumatriptan.

Drug delivery is an important consideration in pain treatment.
Controlled release preparations provide a steady delivery of analgesics.
Well-known non-injection methods such astransdermal, pulmonary and
intranasal application have been used. Topical analgesics and local
anesthetics are also available. Devices such as implanted pumps are used
for delivery of drugs such as opioids intrathecally (introduction into
spinal subarachnoid space by lumbar puncture) in patients with cancer
pain.